EP 2 110 539 A2 describes a filter device for diesel fuel, which device has a ring-shaped filter element in a pot-shaped filter housing, the fuel to be filtered flowing through the filter element radially from the outside to the inside. The filter element has an end disc on each of its axial end faces. The unfiltered fuel is supplied in the region of a first axial end face via a heating module that is flange-mounted to a cover of the filter housing and is retained using a connector. Inserted in the heating module is a feed pipe for connecting to a fuel line, the fuel being conducted on the opposing side of the heating module via another pipe to the radially outwardly disposed unfiltered side of the filter element. A central fitting on the heating module projects into the clean area through an opening in the end disk; the central fitting is part of a pressure gauge device via which it is possible to measure the differential pressure between the unfiltered side and the filtered side. The filtered fluid is conducted away via the end disk of the filter element axially opposing the heating module.